[STABLE v4.9 & v4.14] l2tp: Prevent circular locking and use-afer-free issues

[Lee Jones]

Dear Stable,

Please could you apply the following patches to the v4.9 and v4.14
trees:

  225eb26489d05 l2tp: don't use inet_shutdown on ppp session destroy          
  d02ba2a6110c5 l2tp: fix race in pppol2tp_release with session object destroy

They fix circular locking dependency and use-after-free issues.

Kind regards,
Lee

-- 
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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